Journal of Chemical Ecology (2005) 31, 1953-1967

W.R. Cooper, L. Jia and L. Goggin (2005)
Effects of jasmonate-induced defenses on root-knot nematode infection of resistant and susceptible tomato cultivars
Journal of Chemical Ecology 31 (9), 1953-1967
Abstract: Jasmonates, such as jasmonic acid (JA), are plant-signaling compounds that trigger induced resistance against certain pathogens and a broad range of arthropod herbivores. One goal of this study was to determine the effects of JA-dependent defenses in tomato on root-knot nematodes. Another was to determine if the artificial induction of these defenses could enhance nematode control on plants that carry Mi-1.2, a nematode resistance gene that is present in many tomato cultivars. At moderate soil temperatures, Mi-1.2 can effectively suppress reproduction of most isolates of the common root-knot nematode species Meloidogyne javanica, M. incognita, and M. arenaria. Mi-mediated resistance has its limitations, however. Mi-1.2 is reported to lose its effectiveness at soil temperatures above 28°C, and certain virulent nematode isolates can overcome resistance even at moderate soil temperatures. This study used a foliar application of JA to activate induced resistance in two near-isogenic lines of tomato (Lycopersicon esculentum) with and without Mi-1.2, and evaluated the effects of induced resistance at moderate soil temperatures on one avirulent nematode isolate (M. javanica isolate VW4) and two virulent isolates (M. javanica isolate VW5 and M. incognita isolate 557R). In addition, the effects of induced resistance on avirulent nematode performance were examined at a high temperature (32°C). The results indicate that JA application induces a systemic defense response that reduces avirulent nematode reproduction on susceptible tomato plants. Furthermore, JA-dependent defenses proved to be heat-stable, whereas the effects of Mi-mediated resistance were reduced but not eliminated at 32°C. JA treatment enhanced Mi-mediated resistance at high temperature, but did not suppress either of the virulent nematode isolates tested.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Fiona L. Goggin, W. Rodney Cooper

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Meloidogyne javanica	Tomato (Solanum lycopersicum)
	Meloidogyne incognita	Tomato (Solanum lycopersicum)
	Meloidogyne arenaria	Tomato (Solanum lycopersicum)